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<TITLE>[Chapter 6] 6.2 Labeled Statements</TITLE>
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<td width=171 align=center valign=top><B><FONT FACE="ARIEL,HELVETICA,HELV,SANSERIF" SIZE="-1">Chapter 6<br>Statements and Control Structures</FONT></B></TD>
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<DIV CLASS=sect1>
<h2 CLASS=sect1><A CLASS="TITLE" NAME="JLR2-CH-6-SECT-2">6.2 Labeled Statements</A></h2>

<P CLASS=para>
Zero or more labels can appear before a statement:


<p>
<img align=middle src="./figs/jlr0605.gif" alt="[Graphic: Figure from the text]" width=424 height=25 border=0>

<P CLASS=para>
A label is
defined throughout the block in which it occurs. The names of labels
are independent of all other kinds of names. In other words, if
a label has the same name as a local variable, formal parameter,
class, interface, field variable, or method, there is never any
confusion or interaction between those names.[1] 
For example, the following
code works even though it contains a label and formal parameter
with the same name:

<blockquote class=footnote>
<P CLASS=para>[1] 
Prior to 
version 1.0.2, Java required labels to have names that did not conflict 
with the names of local variables or formal parameters.
</blockquote>
<DIV CLASS=screen>
<P>
<PRE>
public static void main (String[] argv) {
  argv:
    while (true) {
        System.out.println(argv[0]);
        if ( Math.random() &gt;.4)
            break argv;
        System.out.println("Again");
    }
}
</PRE>
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<P CLASS=para>
Labels are used to mark statements, but a labeled statement
does not affect the order of execution when it is defined. The statement
following the label is executed as if the label were not present.
However, a label can be used in a <tt CLASS=literal>break</tt>
or <tt CLASS=literal>continue</tt>
statement to transfer control to a labeled statement. Unlike C/C++,
Java does not have a <tt CLASS=literal>goto</tt> statement.

<P CLASS=para>
<b>References</b>
<A HREF="ch02_02.htm#JLR2-CH-2-SECT-2.1">Identifiers</A>;
<I CLASS=emphasis>Statement</I> 6;
<A HREF="ch06_08.htm#JLR2-CH-6-SECT-8">The break Statement</A>;
<A HREF="ch06_09.htm#JLR2-CH-6-SECT-9">The continue Statement</A>

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<td width=172 align=right valign=top>The Empty Statement</td>
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